The present invention relates to oil-gauges for mounting to a vehicle""s hub to provide a visual indication of the level of oil lubricating the axle-end bearings. More particularly, the oil meter of the invention provides a direct display indicating whether oil needs to be added.
In large and medium-sized vehicles, whether passenger or cargo, it is of particular importance to control that there is enough oil in the hub to adequately lubricate the bearings on each axle end. FIGS. 1A and 2A respectively represent a perspective view and a cross-section view of a conventional aluminum hub 11 known on the market under a STEMCO trademark. The hub 11 includes a chamber 13 housing ball-bearings for supporting a wheel system on the axle end and oil for lubricating the bearings (not illustrated). The oil-gauge includes a glass (i.e. acrylic) lid 15 mounted to the outer end of the hub 11 in a plane perpendicular to the axle 17. The glass 15 seals the outer end of the chamber and is bathed by the oil inside, providing a direct visual display of the oil level inside the chamber 13. The lid 15 has a pair of circular bosses 19A, 19B molded on the glass surface thereof to provide a visual indication of the oil level relative to maximum and minimum levels, respectively. The glass 15 is further gauged with appropriate indicia 21A, 21 B, such as xe2x80x9cFULLxe2x80x9d and xe2x80x9cADDxe2x80x9d, respectively, the latter enabling a driver or operator to immediately asses a need of replenishing oil in the chamber 13.
The above-described oil-gauge is designed to indirectly protect the wheel bearings by providing the driver with a simple and direct means of checking oil level and avoiding that a vehicle wheel run dry, which may result in the bearings locking and thereafter a potentially serious accident.
However, we have found on the road that the conventional gauge display is frequently difficult to read because the oil level is hard to see for lack of contrast, which is further exacerbated as the lid becomes soiled on the inside and therefore has to be dismantled to be cleaned. This operation requires unscrewing.several bolts and we have found that drivers generally find it easier to change the glass 15 rather than to clean it, which is an unnecessary waste.
An object of the invention is an improved oil-gauge for mounting to a hub on the end of an axle which requires less frequent cleaning or replacing in lieu thereof.
Another object of the invention is an oil-gauge less susceptible to soiling inside the oil chamber.
A further object of the invention is an oil-gauge for mounting to a hub on the end of an axle to provide an improved display of the oil level in the hub.
To attain these and other objects and advantages, a portion of the chamber of an oil gauge as generally referred to hereinabove is axially partitioned from the rest of the chamber housing the bearings by an annular disk or the like mounted inside of and parallel to the outer transparent or translucid lid, to form a subchamber in the annular space between the disk and the outer lid wherein oil may flow outwardly from the rest of the chamber, thereby enhancing the visibility of the level of oil in the chamber through the lid. The surface facing the lid outwardly may be coated with white paint or the like to provide a more marked contrast to further enhance the oil level visibility.
Furthermore, the outer subchamber may be dimensioned to be relatively narrow in the axial direction and contain one or more loose elements inside to produce a wiping effect on the inside of the lid during movement, thereby helping to keep the lid inside clean.